Interactive game device and interactive game method combined with child sandbox

The invention discloses an interactive game device and an interactive game method combined with a child sandbox. The method comprises the following steps: connecting a computer to a projector and a motion sensing device; orthographically projecting the projector to the sandbox; obtaining depth image data of sand in the sandbox by the computer through the motion sensing device; calculating, by the computer, topographic and geomorphic data of the sand in the sandbox by virtue of a smooth interpolation algorithm; modifying, by the computer, topographic and geomorphic contents of hills of updated projection according to cumulated sand data; modifying, by the computer, topographic and geomorphic contents of rivers and lakes of the updated projection according to high-cut sand data; checking, by the computer, whether a player stretch out a hand or not on a hill cumulated by sand by virtue of images of the motion sensing device; modifying, by the computer, magmatic explosion image contents of the updated projection according to location data of a hand stretching part of the player; restoring magma in a certain period of time; and ending the game. The interactive game device and the method disclosed by the invention not only can well arouse the interest of children, but also can activate hands-on and cooperation abilities of the children and challenge creative abilities of the children.